Remote-processing BASIC 52 Manuel d'utilisateur télécharger pdf (Page 23)

RPBASIC-52 PROGRAMMING GUIDE

2-4

ATN

Syntax: ATN(expr)

Where: expr = value betw een 0 and PI/2

Function: Returns a trigonometric arc-tangent of expr. Returned result is between -PI/2 and PI/2 radians.

Mode: Command, run

Use: PRINT 4*ATN(1)

Cards: All

DESCRIPTION

SIN, COS, and TAN operators use a Taylor series to calculate the function. These operators first reduce the

argument to a value that is between 0 and PI/2. The algorithm used to reduce the value will reduce accuracy

when expr is large. To maintain accuracy, keep the arguments for trig functions as small as possible.

ERRORS

ARITH. UNDERFLOW expr or result is less than RPBASIC-52's smallest floating-point value of ±1E-127

ARITH. OVERFLOW expr or result is greater than RPBASIC-52's largest floating-point value of

±.9999999E+127

DIVIDE BY ZERO Attempt to take TAN(X) when COS(PI/2) = 0

EXAMPLES

100 PRINT SIN(PI/2),COS(10001*PI),TAN(5*PI/4)

110 PRINT ATN(TAN(PI/4))/PI

>run

1 -1 1

.24999996

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 162 163

Pas de commentaire

Remote-processing BASIC 52 Manuel d'utilisateur Page 23